Evaluation of Multiplex Real-time PCR and WHO Criteria for Diagnosing Childhood Bacterial Meningitis in a Tertiary Referral Hospital in Iran

Background: Childhood bacterial meningitis (BM) requires prompt and precise diagnosis to provide proper treatment and decline mortality and morbidity. Objectives: We aimed to evaluate the World Health Organization (WHO) criteria and polymerase chain reaction (PCR) for diagnosing BM in children admitted to a tertiary referral hospital in Shiraz, southern Iran. Materials: We included all 492 children aged one month to 17 years suspected of meningitis who had cerebrospinal fluid (CSF) leukocytosis admitted to Nemazi Hospital from August 2016 to September 2017. The CSF specimens were examined for routine analysis, Gram staining, and culture. A multiplex real-time PCR was used to identify Streptococcus pneumoniae, Haemophilus influenzae type b (Hib), and Neisseria meningitidis in the CSF samples. Seven viruses were also investigated using real-time PCR. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated using the WHO criteria and the multiplex real-time PCR results. Results: Seventy-four CSF samples had leukocytosis. Nineteen (22.9%) patients had BM caused by S. pneumoniae (n = 14), Hib (n = 2), Salmonella enterica (n = 2), and N. meningitidis (n = 1). The PCR test detected all cases, except for two with Salmonella meningitis (sensitivity 89.4%, specificity 100%, PPV 100%, and NPV 96%). The WHO criteria detected all cases, except three who received antibiotics at least four days before performing lumbar puncture (sensitivity 84.2%, specificity 98.2%, PPV 94.1%, and NPV 94.7%). Enterovirus was the most common viral etiology (6.75%). Conclusions: The WHO criteria and the multiplex real-time PCR had high accuracy in our setting, and their use could decrease the antibiotic over-prescription in febrile children suspected of meningitis.